Characterisation of lotus-leaf-like superhydrophobic fluorinated polysiloxane coating prepared with gradient coating technology

In this study, an original gradient coating method was employed to prepare a superhydrophobic composite coating, using no. 107 silicone rubber/fluorinated polysiloxane mixture as basal glue and modified composite particles as reinforcement. Fourier transform infrared spectroscopy (FTIR) results indicate that the compound particles are successfully modified by hexamethyl disilazane (HMDS) and C–F group is introduced into the basal glue. Scanning electron microscopy (SEM) and contact angle measuring instrument were applied to investigate the micro-morphology and hydrophobic property of the composite coating. SEM result indicates that micro/nano multistage structure is formed which is similar with papillae of lotus leaf. Hydrophobic test result shows that the average and maximum static contact angles are 157·5 and 161·9° respectively. The sliding angle is only 2°. Compared with conventional hydrophobic materials and methods, the low cost and simple production process of this coating make it expected to be applied in many industrialised superhydrophobic fields.